Yakima Basin Beaver

Beaver populations are significantly lower than what was found before European settlement, and continued research shows that salmonids benefit from beaver presence. Streams with extensive beaver impoundments have been shown to increase the densities of juvenile salmonids. Broadly, this project will further build on previous efforts by the YN and partners in the basin to facilitate resilient climate landscapes in the Yakima Basin using low-tech, process-based restoration techniques. Project activities will result in the identification of sites for the future relocation of beavers into appropriate habitats. Future actions will result in reconfiguring floodplains, improving in-stream habitat for salmonids, and helping limit climate change impacts to cold-water fish species of significant cultural importance to the Yakama people. In-stream habitat changes would include; enhanced off-channel habitat, alluvial aquifer recharge, and decreased stream temperatures. Surveys will be conducted by technicians/interns walking stream adjacent to identify current and historic beaver use within areas identified as High or Moderate by the WDFW’s Beaver Intrinsic Potential model. Tracking the number of kilometers of stream surveyed will provide a measurable outcome and reduce the potential for unplanned redundancy with surveys in future iterations. Recent research has demonstrated that the correct identification of suitable habitat before relocation increases the beaver’s success in the immediate area. Completing these surveys will provide information for future beaver relocations, further enhancing cold-water fish habitat in the Yakima River Basin.



Worksite #1 Proposed Work: Naches River Basin Habitat Assessment

Past beaver assessments and relocation efforts were performed in the upper Yakima River Basin from 2013-2015. This work included identification of existing beaver complexes, historic beaver use, fresh sign in new areas, and relocation of beavers trapped from areas where they were in conflict with human activity. During this time there was minimal work done in the Naches River Basin. Since that time the Washington Department of Fish and Wildlife has developed a beaver intrinsic model that helps inform managers of areas where beavers are likely to be found. Using this model with previous survey techniques, we will survey high and moderate probability areas within the Naches River Basin using interns (Mid-Columbia Fisheries Enhancement Group) and fisheries technicians (Yakama Nation staff).

As beavers build and maintain pond complexes water begins to be impounded. Research has shown that this increased impoundment leads to increased groundwater exchange, which helps to reduce water temperatures throughout the year. Additionally, impounded water will aid in reconnecting old and/or seasonal side-channels, increasing rearing habitat for juvenile salmonids. Over time these impoundments begin to trap sediment to reduce long term loss of spawning habitat. Knowledge of beaver benefits to salmon has gained traction in the last decade and as more research is undertaken the understood benefits to salmonids will increase. This project will specifically address PCSRF Priority One and Two.